Pliss Lymphosarcoma Research Articles

Cytotoxicity and antitumor activity of sesquiterpene lactones. Structure, activity

The article discusses the results of 19 samples screening of sesquiterpene γ-lactones argolide, grosheimin, estafiatin, and their derivatives for cytotoxicity and antitumor activity. The research results indicate significant cytotoxicity and selectivity of the action of sesquiterpene γ-lactones and their derivatives against most tumor cell lines. Aim. The purpose of this study is to study the cytotoxicity and antitumor activity of the sesquiterpene γ-lactones argolide, grosheimin, estafiatin and their chemically modified derivatives, as practically renewable materials. Methods. The cytotoxicity of the compounds was determined using vero cells, THP-1, Pliss lymphosarcoma cell lines, Walker carcinosarcoma, sarcoma 45, sarcoma-180, alveolar liver cancer PC-1, P-388 leukemia, L-1210 leukemia, and resistant to 5-fluorouracil sarcoma 45. The antitumor activity of the samples was studied in in vivo experiments on white outbred rats with transplanted tumor strains and was assessed by inhibition of tumor growth and the magnitude of the increase in average life expectancy. Statistical processing of the results was carried out using the program “GraphPad Prism v. 6.0" (GraphPad Software Inc., USA). Conclusion. When determining cytotoxicity in in vitro samples of the sesquiterpene γ-lactones argolide, grosheimin, and estafiatin showed selectivity of their action on cells of 8 tumor lines, on cells of human acute monocytic leukemia THP-1 and in relation to the larvae of sea crustaceans Artemia salina (Leach). Samples of argolide, 8-acetylgrosheimin, 13-morpholinogrosheimin, 3-keto-4-methylene-cis-guaianolide, 3α-acetoxyisozaluzanin C, and 10α(14)-epoxy-1,5,7α,4,6β(H)-guai-11(13)-en-4(3),6(12)-diolide in experiments in vivo possessed high antitumor activity against transplantable tumor strains of Pliss lymphosarcoma, Walker carcinosarcoma, sarcoma 45, sarcoma 37, sarcoma 180, alveolar liver cancer PC-1, leukemia P-388 and L-1210, resistant to 5-fluorouracil sarcoma 45

Combined photodynamic and radiodynamic therapy with a chlorine photosensitizer under fractionated radiation exposure to transplanted tumors in an <i>in vivo</i> experiment

Introduction. The current direction of scientific research in experimental and clinical oncology is radiodynamic therapy (RDT), a treatment method based on the activation of photosensitizers (PS) by ionizing radiation. As the results of in vitro / in vivo studies show, a number of photosensitizing agents have radiomodifying properties, and the method itself is characterized by high antitumor efficacy.Aim. To study the possibility of increasing the effectiveness of photodynamic therapy (PDT) through its combined use with RDT in an in vivo experiment.Materials and methods. The work was performed on 26 white non-linear rats weighing 180 ± 50 g. Pliss lymphosarcoma was used as a tumor model, which was transplanted subcutaneously. The chlorine-based PS (Belmedpreparaty, Republic of Belarus) was administered intravenously at a dose of 2.5 mg / kg of body weight. The RDT session was performed by the contact method (CRT) after 2.5–3, 24 and 48 hours after the end of PS administration on the microSelectron-HDR V3 Digital device (Elekta, Sweden) using γ-radiation (192Ir) in a single focal dose (SFD) of 2 Gy until the total focal dose of 6 Gy is reached. A PDT session was performed once immediately after the first exposure to ionizing radiation using a PDT diode laser (Imaf Axicon, Republic of Belarus, λ = 660 ± 5 nm) at an exposure dose of 100 J / cm² with a power density of 0.2 w / cm² and a power of 0.353 w. All rats were divided into 4 groups of 6–7 animals each: intact control, PS + PDT, PS + CRT, PS + CRT + PDT. The criteria for evaluating antitumor efficacy were: the average volume of tumors (Vav), the coefficient of absolute growth of tumors (K), the coefficient of tumor growth inhibition (TGI), the frequency of complete tumor regressions (CR), the proportion of cured rats, an increase in the average duration of dead rats. Differences were considered statistically significant at p <0.05.Results. On the 18th day of the experiment, Vav in groups was 65.98 ± 0.81 cm³; 24.02 ± 4.01 cm³ (р <0.00001); 17.11 ± 4.13 cm³ (р <0.00001); 4.42 ± 1.65 cm³ (р <0.00001), respectively. Coefficients K – 5497.33 OE; 1714.71 OE; 1424.83 OE; 367.33 OE. TGI coefficients – 63.60 % (PS + PDT); 74.07 % (PS + CRT); 93.30 % (PS + CRT + PDT). An in crease in the average duration of dead rats indicator – 25.31 % (PS + PDT); 55.06 % (PS + CRT); 158.22 % (PS + CRT + PDT). On the 60th and 90th days of the experiment, the frequency of CR and the proportion of cured rats were the same and amounted to 0; 16.7; 14.3 and 42.9 %, respectively.Conclusion. The results obtained indicate that the chlorine PS has, in addition to photosensitizing properties, also radiomodifying properties, and the developed method of combined therapy is characterized by high antitumor efficacy.

Experimental in vivo studies of the antitumor efficacy of photodynamic and radiodynamic therapy and their combinations

The authors studied the antitumor efficacy of photodynamic therapy (PDT) in combination with radiodynamic therapy (RDT) in an in vivo experiment. The study was approved by the Ethics Committee of the N.N. Alexandrov National Cancer Center of Belarus (protocol dated February 25, 2022, № 180). The work was performed on 26 white non-linear rats weighing 200 ± 50 g. Pliss lymphosarcoma (PLS) was used as a tumor model, which was transplanted subcutaneously. Photosensitizer (PS) «Photolon» (RUE «Belmedpreparaty», Belarus) was administered intravenously at a dose of 2.5 mg/kg of body weight. The RDT session was performed by the contact method (CRT) once 2.5–3 times after the end of the infusion of the PS on the «microSelectron-HDR V3 Digital apparatus» (Elekta, Sweden) using γ-radiation (192Ir) in a single focal dose 6 Gy. A PDT session was performed once immediately after exposure to ionizing radiation using a «PDT diode laser» (LTD Imaf Axicon, Belarus, λ=660±5 nm) at an exposure dose of 100 J/cm2 with a power density of 0.2 W/cm2 and a power of 0.353 watts. All rats were divided into 4 groups of 6–7 animals each: intact control (IC), PS + PDT, PS + CRT, PS + CRT + PDT. The criteria for evaluating antitumor efficacy were: the average volume of tumors (Vav, cm3 ), the coefficient of absolute growth of tumors (K, in RU), the coefficient of tumor growth inhibition (TGI, %), the frequency of complete tumor regressions (CR, %), the proportion of cured rats (%), an increase in the average duration of dead rats (%). Differences were considered statistically significant at p<0.05. On the 18th day of the experiment, Vav. in groups was 63.25±2.76 cm³; 29.03±6.06 cm³ (p=0.0002); 22.18±5.94 cm³ (р<0.0001); 11.76±3.29 cm³ (p=0.0000), respectively. Coefficients K – 4516.86 RU; 2638.09 RU; 2024.45 RU; 979.00 RU. TGI coefficients – 54.10% (PS + PDT); 64.93% (PS + CRT); 81.41% (PS + CRT + PDT). An increase in the average duration of dead rats indicator – 48.57% (PS + PDT); 60.00% (PS + CRT); 97.71% (PS + CRT + PDT). On the 60th and 90th days of the experiment, the frequency of PR and the proportion of cured rats were the same and amounted to 0%; 16.7%; 14.3%, and 28.6%, respectively. The results obtained indicate the prospects and relevance of further research in this scientific direction.

Adjuvant composite cold atmospheric plasma therapy increases antitumoral effect of doxorubicin hydrochloride.

Cancer is a global health concern, with a significant impact on mortality rates. Despite advancements in targeted antitumor drugs, the development of new therapies remains challenging due to high costs and tumor resistance. The exploration of novel treatment approaches, such as combined chemotherapy, holds promise for improving the effectiveness of existing antitumor agents. Cold atmospheric plasma has demonstrated antineoplastic effects in preclinical studies, but its potential in combination with specific ions for lymphosarcoma treatment has not been investigated. An in vivo study was conducted using a Pliss lymphosarcoma rat model to evaluate the antitumor effects of composite cold plasma and controlled ionic therapy. Groups of rats were exposed to composite cold plasma for 3, 7, and 14 days, while the control group received no treatment. Additionally, a combination of chemotherapy with cold plasma therapy was assessed, with doxorubicin hydrochloride administered at a dosage of 5 mg/kg. PERENIO IONIC SHIELD™ emitted a controlled ionic formula during the treatment period. The in vivo study demonstrated tumor growth inhibition in groups exposed to composite cold plasma for 3, 7, and 14 days compared to the control group. Furthermore, combining chemotherapy with cold plasma therapy resulted in a threefold reduction in tumor volume. The most significant antitumor effects were observed when doxorubicin hydrochloride at a dosage of 5 mg/kg was combined with 14 days of PERENIO IONIC SHIELD™ ionic therapy. The use of composite cold plasma therapy, in conjunction with a controlled ionic formula emitted by PERENIO IONIC SHIELD™, in the complex treatment of lymphosarcoma in rats showed promising antitumor effects. The combination therapy, particularly when combined with doxorubicin hydrochloride, demonstrated enhanced efficacy. These findings suggest the potential for utilizing cold atmospheric plasma and controlled ions as an adjunctive treatment approach in lymphosarcoma therapy. Further research is warranted to explore the mechanisms underlying these effects and to evaluate the safety and efficacy in human clinical trials.

Zonal pattern of blood flow distribution in the Pliss lymphosarcoma microcirculatory bed caused by single exposure of high-intensity focused ultrasound

Introduction. Cell damage is not the only important mechanism of high-intensity focused ultrasound (HIFU) for cancer therapy; concomitant microcirculation disorders having alterations patterns not studied enough also have high significance. The aim of the study was to analyze perfusion along the tumor perimeter depending on the HIFU exposure. Materials and methods. We used a stand for HIFU therapy (MTL LLC). Mode: 8.2 kW/cm2 intensity at 0.6 mm focal spot at 1.4 MHz, exposure time: 150, 200, 250 and 500 ms. The object of the study is the vascular bed of Pliss lymphosarcoma. Tumor tissue temperature was monitored by a T-8 thermograph (Russia), blood flow was measured by the BLF21 laser Doppler recorder (USA). Results. After HIFU exposure time from 150–250 ms, perfusion was noted to have decreased to 1.06 perfusion units (pf.u) in the central zone (p<0.01) compared to the control, but by the 30 min perfusion has increased to 1.22 pf.un. No signs of perfusion improvement were found in exposure time of 500 ms. In the peripheral zone, against the background of a decrease in blood flow to 3.6 pf. u. (p < 0.05) by 30 min of the experiment, hyperperfusion was restored to 5.86 pf. u. in all exposure time. In the central zone, a sharp decrease in microcirculation was observed, probably caused by damage of blood vessels; in the periphery of the tumor, perfusion changes had a phasic and reversible pattern. Conclusion. An increase of HIFU exposure correlates with an increase of temperature of Pliss lymphosarcoma tissue near the focus of exposure. Specific perfusion changes are recorded in the central and peripheral zones of the tumor when single exposed to HIFU with different time exposure; the severity of changes depends on ultrasound exposure-time and is characterized by a zonal pattern of blood flow distribution due to the formation of zones of irreversible and reversible damage to microcirculation.

Radiodynamic Therapy with Chlorine-Based Photosensitizer on Pliss Lymphosarcoma Solid Tumor: In Vivo Experiment

The aim of this study was to investigate the antitumor efficacy of radiodynamic therapy (RDT) with a chlorin-based photosensitizer (PS) in an in vivo experiment.
 Material and Methods: The study was performed in 35 white outbred rats weighing 180±30 g. Subcutaneously transplanted Pliss lymphosarcoma (PLS) was used as tumor model. Chlorin-based PS «Photolon» (RUE «Belmedpreparaty», Republic Belarus) was injected intravenously at a dose of 2.5 mg/kg. The radiation therapy sessions (RT) were carried out once 2.5–3 hours after the administration of the PS by the contact method on the device «microSelectron-HDR V3 Digital» (Elekta, Sweden) using γ-radiation (192Ir) in single focal doses (SFD) 2, 4 and 6 Gy. All laboratory animals were subdivided into 7 groups of 5 animals each: intact control, RT 2 Gy, RT 4 Gy, RT 6 Gy, PS + RT 2 Gy, PS + RT 4 Gy and PS + RT 6 Gy. The antitumor effectiveness of exposure was evaluated according to the indicators characterizing the dynamics of volume changes: Vav. (cm3), the coefficient of absolute tumor growth (K, units) and the coefficient of tumor growth inhibition (TGI, %). The frequency of complete regressions (СR) was estimated 60 days after the performed exposures. In each group, the share of animals (%) with no visual and palpatory signs of tumor growth was evaluated. The differences were considered statistically significant at the significance level of p<0.05.
 Results: On the 16th day from the beginning of the experiment Vav. in groups were 39.07±4.19; 23.06±3.25 (р=0.012); 35.04±2.35 (р=0.419); 25.83±3.06 (р=0.027); 28.36±3.45 (0.074); 25.47±1.88 (р=0.013) and 16.56±3.64 cm3 (р=0,002), respectively. The K coefficients in the experimental groups were 1219.94; 657.86; 1296.78; 716.50; 833.12; 669.26 and 590.43 units, respectively. The TGI coefficients in the experimental groups were 40.98%; 10.31%; 33.89%; 27.41%; 34.81% and 57.61%, respectively. The frequency of complete tumor regressions 60 days after the start of the experiment was 0%, 20%, 0%, 0%, 0%, 0% and 40%, respectively.
 Conclusion: RDT is a recent extension of conventional photodynamic therapy, in which visible/near infrared light irradiation is replaced by a well-tolerated dose of X-rays. Systemic administration of chlorin-based PS before the RT session increases the antitumor efficacy of RT in animals with PLS transplantable tumors. The data obtained indicate that further studies of the radiosensitizing properties of PS are promising.

In Vivo Antitumoral Effects of Linseed Oil and Its Combination With Doxorubicin.

Linseed oil (LO) is known for its exceptional nutritional value due to the high content of alpha-linolenic acid (ALA), an essential omega-3 polyunsaturated fatty acid; its anticarcinogenic effect has been established in several experimental and epidemiological studies. As an adjuvant of chemotherapeutic agents, LO and other ALA-rich vegetable oils have been studied in only a handful of studies at the experimental level. However, the efficacy of antitumoral therapy using doxorubicin (Dox) in combination with ALA and ALA-rich substrates has not yet been investigated. In this work, the antitumor activity of LO in a wide dose range was studied with monotherapy and combined with Dox in animal models with Pliss lymphosarcoma (PLS) and Lewis lung adenocarcinoma (LLC). It was founded the daily oral administration of LO (1, 3, and 10 ml per 1 kg) to rats (PLS) and 6 ml/kg to mice (LLC) for 11–12 days from 7 days after subcutaneous transplantation of tumors has a stable statistically significant effect on the dynamics of tumor growth, reducing the intensity of tumor growth and increasing the frequency of complete tumor regressions (CR) compared with the control. LO showed high antimetastatic activity in the LLC model. Furthermore, LO at a dose of 3 ml/kg potentiates the antitumor effect of Dox in the PLS model, reducing the volume of tumors at the end of treatment by 2.0 times (p = 0.013), the value of the tumor growth index by 1.6 times (p < 0.03) and increasing the frequency of CR 60 days after the start of therapy by 3.5 times (p = 0.019) compared with the use of Dox alone. The combination of Dox and LO or fish oil allows growing efficiency therapy of LLC in comparison with Dox alone, increasing the frequency of CR to 73.68% and 94.4%, respectively, and reducing the frequency of metastasis to zero.

Antitumor efficiency of sonodynamic therapy in combination with chlorine-based photosensitizer in experiments

Introduction. Sonodynamic therapy is a topical research area in experimental oncology. The method is based on the combined use of photosensitizing agents with ultrasonic radiation with certain parameters. The result of this interaction is the induction of sonochemical reactions and the effect of cavitation in the tumor cell. The consequence is its death (apoptosis, autophagy).The study objective is to investigate the antitumor efficacy of sonodynamic therapy with a chlorine-based photosensitizer (PS) in an experiments on laboratory animals with transplantable tumors.Materials and methods. The experimental study was performed on 50 white outbred rats weighing 250 ± 50 grams. Subcutaneously transplanted Pliss lymphosarcoma (PLS) and alveolar liver cancer RS1 (RS1) were used as tumor models. Chlorine-based PS (Belmedpreparaty, Republic Belarus) was injected intravenously at a dose of 2.5 mg / kg. The ultrasound sessions (US) were carried out 2.5–4 hours (depending on the tumor strain) after the administration of the PS using the device Phyaction U (Gymna Yniphy, Belgium) with frequencies of 1.04 and 3 MHz, intensity of 2 W / cm2 and duration of 10 minutes in continuous mode. For each of the tumor model the study was performed on 25 laboratory animals subdivided into groups of 5 individuals: intact control, US 1.04 MHz; US 3 MHz; PS + US 1.04 MHz and PS + US 3 MHz. The criteria for assessing the antitumor efficacy were indicators of the dynamics of the growth of transplanted tumors: аverage volume of tumors (Vav, cm3), the coefficient of tumor growth inhibition (TGI, %), coefficient of absolute growth of tumors (K) and the frequency of complete regressions 60 days after treatment (%).Results. For PLS Vav in groups were 32.72 ± 7.23; 26.81 ± 1.06; 14.80 ± 5.08; 9.37 ± 6.05 and 22.25 ± 4.91 cm3, respectively (p ˂0.05). The coefficients TGI in the experimental groups were 20.27; 54.77; 71.36 and 31.99 %, respectively. Indicators K in groups were 21.64; 14.52; 6.12; 4.91 and 15.34, respectively. The frequency of complete tumor regressions 60 days after the start of the experiment was 0, 20, 20, 40 and 0 %, respectively. For RS1 Vav in groups were 23.29 ± 5.11; 6.22 ± 2.22; 11.78 ± 4.57; 6.38 ± 2.57 and 13.06 ± 3.53 cm3, respectively (p ˂0.05). The coefficient of TGI in the experimental groups were 73.25; 49.42; 72.60 and 43.92 %, respectively. Indicators K in groups were: 8.34; 1.11; 3.39; 2.91 and 5.05, respectively. The frequency of complete tumor regressions 60 days after the start of the experiment was 0, 0, 0, 40 and 0 %, respectively.Conclusions. The data obtained indicate a trend towards an increase in the antitumor effectiveness of the combined use of PS and sonodynamic therapy on various histological structures and growth patterns of transplanted tumors, as well as the prospects for further studies of the sonosensitizing properties of photosensitizing agents.

Syntheses Based on 3,4α-Epoxy-1,5,7α,6β(H)-guai-10(14),11(13)-dien-6,12-olide.

The sesquiterpene γ-lactone estafiatin 1, the molecule of which has a structure of 3,4α-epoxy-1,5,7α,6β(H)-guai-10(14),11(13)-dien-6,12-olide, is characteristic of plants of the genera Achillea L. and Artemisia L. of the Asteraceae family. This article presents the results of chemical modification for three reaction centers of the estafiatin molecule 1: epoxy cycle, exomethylene group conjugated with γ-lactone carbonyl, and exomethylene group in position C10=C14; and at the same time 33 new derivatives were synthesized, the structures of which were established based on physicochemical constants, spectral data (IR-, PMR-, 13C-NMR), and X-ray diffraction analysis. The stereo- and regiospecificity, as well as the chemoselectivity of the reaction based on estafiatin molecule 1, are discussed. The reactivity of the substrate is significantly influenced by the stereochemistry of its molecule, the nature of the reagent, and the reaction medium. Based on the results of in silico screening, derivatives of estafiatin with high binding energies for both DNA-topoisomerase I and DNA-topoisomerase II were identified. The values of the inhibitory dose of IC50 for estafiatin 1 and its derivatives were determined on cell lines of eight types of tumors. in vivo experiments of the samples made it possible to establish that estafiatin 1 and its derivatives have pronounced antitumor activity against Pliss lymphosarcoma, Walker’s carcinosarcoma, sarcoma 45, sarcoma-180, alveolar liver cancer PC-1, leukemia P-388 and L-1210, and sarcoma-45 resistant to 5-fluorouracil.

Synthesis and biological evaluation of new derivatives of grossheimin

Grossheimin 1 is a polyfunctionalized sesquiterpene, featuring, in addition to the exomethylene-γ-lactone group, also an additional exocyclic double bond, a hydroxyl, and a ketone carbonyl. These functional groups have been modified, generally in an orthogonal way, by arylation of the exomethylene, by the introduction of heteroatoms associated to oxygen-, nitrogen- and phosphorous functionalities, and by acylation. A selection of the analogues was investigated for bioactivity, showing that the introduction of a substituent at C-13 is not detrimental, and can modulate potency independently from retention or reduction of the C-11 – C-13 exomethylene double bond and the effect of this maneuver on Michael reactivity.In vivo experiments of 26 samples made it possible to establish that grossheimin 1 and its five new derivatives have a pronounced antitumor activity against alveolar liver cancer, Pliss lymphosarcoma, Walker's carcinosarcoma, sarcoma 45, M-1 sarcoma, P-388 leukemia.

Chartolepis intermedia Boiss. and Centaurea ruthenica Lam. – New Medicina Plants Containing Pharmacologically Active Compounds

BACKGROUND: Chartolepis intermedia Boiss. and Centaurea ruthenica Lam. are new medicinal plants containing pharmacologically active sesquiterpene lactones grossheimin and cynaropicrin. The article discusses the methods for the isolation of grossheimin and cynaropicrin and presents the results of studying the pharmacological activity of the isolated sesquiterpene lactones. AIM: The aim of this work was chemical, morphological, and anatomical study of Ch. intermedia Boiss. and C. ruthenica Lam., determination of pharmacological activity to substantiate the possibility of using these plants as medicinal raw materials. METHODS: The antitumor activity of grossheimin was studied in white outbred rats and mice in 12 strains of transplanted tumors. The antiparasitic activity of grossheimin and cynaropicrin was studied during replication of models of experimental opisthorchiasis on male golden hamsters (Mesocricetus auratus) of the SPF category. Experiments in vivo were carried out on pastoral dogs infested with various types of helminths. The hypolipidemic activity of grossheimin was studied in experimental rats with a single intragastric administration of ethanol, causing acute hyperlipidemia. The antimicrobial activity of cynarpicrin was determined in relation to test strains of Gram-positive bacteria Staphylococcus aureus and Bacillus subtilis and Gram-negative strains of Escherichia coli and Pseudomonas aeruginosa by the method of diffusion in agar. RESULTS: Characteristic diagnostic features for Ch. intermedia Boiss. and C. ruthenica Lam. were revealed, which make it possible to diagnose and standardize the medicinal plants under study. Pharmacological studies have shown that grossheimin and cynaropicrin have antitumor, antiparasitic, hypolipidemic, and antimicrobial activity. Grossheimin significantly inhibits the growth of sarcoma 180, Pliss lymphosarcoma, and Ehrlich’s solid tumor. On the model of acute hyperlipidemia caused by the introduction of ethanol, grossheimin had a hypolipidemic effect, reducing the serum levels of triacylglycerides, total cholesterol, and low-density lipoprotein cholesterol. Under in vitro conditions, grossheimin and cynaropicrin exhibited anthelmintic action against Opisthorchis felineus worms, and under in vivo conditions, cynaropicrin was up to 100% effective against tapeworm infections (Taenia sp.). CONCLUSION: It was determined that the quantitative yield of sesquiterpene lactones is provided by extraction of plant raw materials with an ethanol: water (1:1) mixture under the action of ultrasound. Characteristic diagnostic features for C. intermedia Boiss. and C. ruthenica Lam. were revealed, which make it possible to diagnose and standardize the medicinal plants under study.

Applicability of mitochondrial energy factors in accompanying therapy of lymphoproliferative diseases (experimental study)

Aim. The purpose of the study was to reveal the effectivenessof the Cytochrome C drug in the early stages of the Pliss lymphosarcomagrowth in white outbred rats.Material and methods. The studies were included white outbredmale rats with an initial weight of 180–220 g (n = 40) withsubcutaneously inoculated Pliss lymphosarcoma. Rats in themain group received the Cytochrome C intraperitoneally in asingle dose of 1.6 mg/kg 1 hour after the tumor inoculationand then until death; animals with tumors in the control groupreceived saline instead of the studied drug in the same way andin the same dosage.Results. Subcutaneous tumors appeared in the control groupin 100% cases, in the main group in 55% cases; tumors werenot detected in 45% of animals in the main group. In rats ofthe main group receiving experimental treatment, tumors regressedwith time: in 73% cases with complete recovery of rats,in 27% cases animals died.Conclusions. The Cytochrome C in a therapeutic and prophylacticregimen had a pronounced antitumor effect. Perhaps theeffectiveness of the drug can be improved using an inert carrierwhich will protect the protein from proteolytic cleavage whenit enters the bloodstream, together with detoxification agents.

Antitumor efficiency of contact radiotherapy in combination with a chlorin-based photosensitizer in experiment

Authors have studied the antitumor efficacy of contact radiation therapy (CRT) in combination with a chlorin-based photosensitizer (PS) in an experiment on laboratory animals with transplanted tumors. The experimental study was performed in 50 white outbred rats weighing 250±50 g. Subcutaneously transplanted Pliss lymphosarcoma (PLS) and alveolar liver cancer RS1 (RS1) were used as tumor models. Chlorinbased PS photolon (RUE «Belmedpreparaty», Republic Belarus) was injected intravenously at a dose of 2.5 mg/kg. The radiation sessions were carried out 2.5–4 hours (depending on the tumor model) after the administration of the PS using the device «microSelectron HDR V3 Digital» («Nucletron», Netherlands) with a 192-Ir radiation source in single focal doses 5 and 10 Gy. All laboratory animals (for PLS and RS1) were subdivided into 5 groups of 5 animals each: intact control, CRT 5 Gy, CRT 10 Gy, PS + CRT 5 Gy, PS + CRT 10 Gy. For the PLS tumor model – on the 14th day from the beginning of the experiment Vav. in groups were 26.31±5.81; 22.45±6.97; 18.99±4.86; 10.75±5.18 and 28.06±2.85 cm3, respectively (p˂0.05). The coefficients of tumor growth inhibition in the experimental groups were 14.67%, 27.82%, 59.14% and 6.65%, respectively. The frequency of complete tumor regressions 60 days after the start of the experiment was 0%, 20%, 20%, 60%, and 20%, respectively. On RS1 tumor model – on the 14th day from the beginning of the experiment Vav. in groups were 4.48±1.03; 0.80±0.21; 0.29±0.09; 0.19±0.07 and 0.32±0.08 cm3, respectively (p=0.009). The coefficients of tumor growth inhibition in the experimental groups were 82.14%, 93.53%, 95.76% and 92.86%, respectively. The frequency of complete tumor regressions 60 days after the start of the experiment was 0%, 0%, 20%, 0%, and 0%, respectively. Systemic administration of chlorin-based PS before the CRT session increases the antitumor efficacy of radiation therapy in animals with transplantable tumors of different histological structure and growth patterns. The data obtained indicate that further studies of the radiosensitizing properties of PS are promising.

ФОТОДИНАМИЧЕСКАЯ ТЕРАПИЯ В КОМПЛЕКСНОМ ЛЕЧЕНИИЛИМФОСАРКОМЫ ПЛИССА И РАКА ШЕЙКИ МАТКИ-5

Background. Malignant tumors management using conventional treatment modalities is associated with poor outcomes. Objective of the study. To assess photodynamic activity of Photolon as monotherapy, as well as in combination with radio- and chemotherapy in an experiment.Material and methods. The research was done on HeLa monolayer culture (human uterine cervix carcinoma), 97 white random-bred rats with Pliss lymphosarcoma and 42 mice (CBA) with uterine cervix cancer-5 (UCC-5). Results. The amplification factor in Photolon photoirradiation was 65.1 in terms of the cytostatic effect and 98.5 in terms of cytotoxic effect. Photodynamic therapy enhances the efficacy of radiotherapy, since it reduced Pliss lymphosarcoma growth rate in rats down to 33.7% and UCC-5 growth rate in mice down to 14.9% of the intact control level (p&lt;0.05). Conclusion. It is advisable to include photodynamic therapy in multimodality treatment.

Физико-химические и биологические свойства ассоциатов наночастиц меди

Проведено исследование физико-химических параметров ассоциатов не стабилизированных наночастиц (НЧ) меди, полученных плазмохимическим способом. Для определения размеров ассоциатов НЧ использовали оптические методы, включая атомно-силовую микроскопию, спектрофотометрию и флюорометрию. Размеры НЧ меди варьировали от 30 до 75 нм, а размеры ассоциатов НЧ — от 481.1 до 1037 нм. Проведен анализ фазового состава НЧ меди методом рентгеновской дифрактометрии с использованием многофункционального рентгеновского дифрактометра Rigaku Ultima IV. На поверхности ассоциатов НЧ обнаружена оксидная пленка без примеси органических молекул. Изучали действие НЧ меди на культуру клеток А549. Обнаружено изменение биохимических показателей сыворотки крови белых беспородных мышей под влиянием НЧ меди. Выявлен противоопухолевый эффект НЧ меди и сопоставлена его выраженность при разных способах введения НЧ животным с фибросаркомой (С-45) и лимфосаркомой Плисса.

PHYSICOCHEMICAL AND BIOLOGICAL PROPERTIES OF ASSOCIATES OF COPPER NANOPARTICLES

Abstract—The physicochemical parameters of associates of unstabilized copper nanoparticles (NPs) obtained by the plasma-chemical method were studied. Optical methods were used to determine the size of NP associates, including atomic force microscopy, spectrophotometry, and fluorometry. The sizes of copper NPs varied from 30 to 75 nm, and the sizes of NP associates, from 481.1 to 1037 nm. The phase composition of copper NPs was analyzed by X-ray diffractometry using a Rigaku Ultima IV multifunctional X-ray diffractometer. An oxide film without an admixture of organic molecules was found on the surface of NP associates. The effect of copper NPs on an A549 cell culture was studied. A change was observed in the biochemical parameters of blood serum of outbred mice under the influence of copper NPs. The antitumor effect of copper NPs was revealed, and its intensity was compared to different methods of administering NP to animals with fibrosarcoma (S-45) and Pliss lymphosarcoma.

Возможности использования «Натрия фторида, 18F» для диагностики опухолей в костях методом позитронной эмиссионной томографии (экспериментальное исследование)

Purpose: To study the potential of using radiopharmaceutical “Sodium Fluoride 18F” in order to reveal foci of malignant tumors in animals’ bones by positron emission tomography (PET).&#x0D; Material and methods: Two experimental models (human prostate adenocarcinoma PC 3 and Pliss lymphosarcoma) were used. Tumor cell PC 3 suspensions were injected under a hip periosteum of the BALB/c nude line mice or outbred rats (Pliss lymphosarcoma). Radiopharmaceutical was injected into a tail vein of animals with developed tumors. Then PET scanning was performed for these animals.&#x0D; Results: Effective half-life of radiopharmaceutical from blood was 9.45 min, from skeleton bones - 77.5 min and tumors – 99 min. The hyperfixation level of radiopharmaceutical in the tumor was sufficient to image tumors by PET. In areas of the tumor from cells of prostate adenocarcinoma PC 3 and Pliss lymphosarcoma the uptake rate of radiopharmaceutical was quite high during an hour that resulted in a high contrast image of tumors in animals’ bones. T/NT ratio tumor/bone in rats with Pliss lymphosarcoma was increased in the first 20 min after administration of the radiopharmaceutical, and then slowly decreased. Nevertheless, in 40 minutes after injection of the radiopharmaceutical T/NT ratio tumor/bone remained quite high – more then 1.7, and T/NT ratio tumor/muscle exceeded to 9.0.&#x0D; Conclusion: The uptake level and fixation time of the radiopharmaceutical in tumor foci, as well as low activity value and its rapid excretion from intact tissues show the expediency of the use of “Sodium Fluoride 18F” to diagnose intraosseous foci of malignant diseases.

Factors and conditions affecting the antitumor effect of magnetite nanoparticles in the experiments in vivo.

e14051 Background: Independent antitumor effects of magnetite nanoparticles (NPs) in animals, up to complete regression of large tumors, have been demonstrated. Factors and conditions that contribute to the appearance and enhancement of such effects are an important issue. Our purpose was to study the dependence of antitumor effects of magnetite NPs on characteristics of animals, ways of preparation and injection of NPs and weak magnetic fields (WMF). Methods: The experiment included 380 white outbred rats with transplantable sarcoma 45 (S45), Pliss lymphosarcoma (PL) and Heren carcinoma (HC) and 230 С57Black/6 mice with B16 melanoma. The animals received 6-8 1.25-35.4 mg/kg peritumoral or intraperitoneal injections of a water-based magnetite NP ferrofluid (FF) diluted with saline solution. WMF parameters were: 0.03-9 Hz frequency, 0.7-3.2 mT induction, exposure on the head. Dynamics of tumor sizes, histological changes and FF characteristics after the dilution with saline (X-ray absorption spectroscopy analysis) were evaluated. Results: An effective single dose in S45 female rats with peritumoral injections was higher than in males (35.4 and 17.7 mg/kg, respectively). Female rats with HC were sensitive to small NP doses (1.25 mg/kg) in intraperitoneal (but not peritumoral) injections (regression in &gt; 30%). Peritumoral injections of small NP doses were most effective in PL males, while a number of experiments did not show benefits of small NP doses for mice. NP solution storage led to its lower effect due to the oxidation of Fe +2 to Fe +3, and even FF dilution ex tempora decreased the effect as SS pH changed to 7.4. WMF was able to enhance the effect of NPs by up to 1.5 times but not in intraperitoneal injections. Conclusions: Antitumoral effects of NPs depended on species of animals and their gender, tumor types, doses and methods of NP injections, storage time of diluted FF prior to its injection, saline pH, and WMF. WMF effects were different depending on NP injection methods.

Effect of iron nanoparticles on free radical oxidation process in blood of rats with Pliss lymphosarcoma

The use of metal nanoparticles (NPs) for cancer treatment requires careful examination of their biological effects. The aim of this study was to determine parameters of oxidative processes in the blood of tumor-bearing animals treated with metallic iron NPs only. The markers of antioxidant status and accumulation of lipid peroxidation products were measured in erythrocytes and blood plasma of rats with Pliss lymphosarcoma (PLS) and intact rats. PLS animals were treated eight times with iron NPs (at a dose of 1.25 mg/kg bw (main group), rats of the control group received saline (0.3 ml). In control animals, an increase in malondialdehyde (MDA) was observed in red blood cells (RBC) by 45%; this was accompanied by compensatory increase in reduced glutathione (GSH) and catalase by 24% and 14.3%, respectively (p<0.05). In plasma an increase in MDA by 167.4% (p<0.01) and a decrease in oxidase activity of ceruloplasmin (CP) by 36.8% (p<0.001) were found. In the main group there was a decrease of accumulation of lipid peroxidation products in the blood. Intensity of detected changes depended on the antitumor effect: rats with growing LSP showed a tendency to the decrease in the RBC MDA level and normalization of plasma MDA; in animals with LSP regression this marker did not differ from normal values. In all animals of the main group the CP content was basically the same as in intact rats while GSH increased in the group without therapeutic effect (by 218.6%) and in the group with the effect by 69% (versus normal values; p<0.01). SOD activity in the rats with LSP growth significantly increased (by 42%), in the rats with regression decreased (by 30%) with subsequent normalization. Thus, administration of iron NPs caused activation of the antioxidant system in blood and a significant decrease in the manifestations of oxidative stress associated with tumor growth.

A66: Changes in experimental tumors and surrounding tissue under antitumor influence of magnetite nanoparticles introduced into the peritumoral area

Background In previous experiments the self-dependent antitumor effect of magnetite nanoparticles (NPs) injected in peritumoral area in form of magnetic fluid (MF) was shown. Elucidation of the mechanisms of this phenomenon is of theoretical and practical interest. The aim of the study was to investigate the cellular and ultrastructural changes in the tissue tumors regressed under the influence of magnetite NPs, as well as the composition of the cells of the immune system in the peritumoral area. Materials and methods The study was carried on white male rats, 180–200 g, with transplanted sarcoma 45 (59) or Pliss lymphosarcoma (50). Special antitumor agents were not used. Magnetite NPs (10 ± 2 nm) were applied in the form of the water-based MF. Original MF (20 kA/m) was diluted with saline in different degree and was injected into peritumoral zone along the tumor borders at a distance of 1.5 cm twice a week in a volume of 0.4–0.9 ml (depending on the animal weight) within 3 weeks. Special anti-tumor agents were not used. At the end of the experiments fragments of the tumor and surrounding tissue were taken for research. The study of changes in the tumor and peritumoral area were performed by the methods of cytology, histology, histochemistry, electron microscopy (microscope JEOL JEM-1011, Japan), flow cytometry, X-ray fluorescence spectroscopy (spectrometer M4 Tornado Bruker). Results At a dilution of the original MF in 30 times the treatment was effective in 75% of animals. Complete and partial (more than 2-fold) tumor regression was observed in 2/3 cases. In rats with Pliss lymphosarcoma tumor regression on 70–100% has been reported in 20–40% cases. The results of microscopic examination of sarcoma 45 with partial regression showed significant changes in their immune microenvironment compared with the cases of progressive tumor growth (p Conclusion The study results reflect the changes in the immune microenvironment of experimental tumors under effective action of magnetite NPs and indicate significant activation of local immune processes caused by these factors.